@article { ISI:000358337700009,
	title = {Synthesis, optoelectronic, and transistor properties of BODIPY- and cyclopenta[c]thiophene-containing pi-conjugated copolymers},
	journal = {Journal of Physical Chemistry C},
	volume = {119},
	number = {28},
	year = {2015},
	month = {JUL},
	pages = {15859-15867},
	publisher = {AMER CHEMICAL SOC},
	address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA},
	abstract = {<p>Three new low-band-gap copolymers were synthesized by fusing dipyrromethene difluoroborane (BODIPY) as the acceptor (A) and thiophene-capped 5,5-bis(hexyloxymethyl)-5,6-dihydro-4H-cyclopenta[c]-thiophene (CPT) as the donor (D). The BODIPY unit was copolymerized through the {\textquoteleft}alpha{\textquoteright} positions (1 and 7 positions) in P1 and through the {\textquoteleft}beta{\textquoteright} positions (2 and 6 positions) in P2 and P3. The additional acetylene unit between D and A in P3 enhanced the conjugation by minimizing the possible steric hindrance compared to that in P2, whereas P1 exhibited a more red-shifted absorption than P2 and P3 because of the more effective conjugaion through the {\textquoteleft}alpha{\textquoteright} positions of BODIPY. Importantly, the optical band gaps (E-g(opt)) obtained from the onset of the absorption spectra are 1.28, 1.71, and 1.57 eV for P1, P2, and P3, respectively. P1 has the lowest band gap for any CPT-containing polymer. In the best transistor devices, a mobility improvement by 4 orders of magnitude from 3.22 x 10(-6) cm(2) V-1 s(-1) for P2 to 0.01 cm(2) V-1 s(-1) for P1 was achieved. DFT calculations alongside measured charge-transport properties indicated that appreciable alterations in the optoelectronic properties of the polymers were achieved through minor changes in their structural features. The polymers were further characterized by thin-film X-ray diffraction, atomic force microscopy, and spectroelectrochemistry to investigate their material and electrochemical properties.</p>},
	issn = {1932-7447},
	doi = {10.1021/acs.jpcc.5b02743},
	author = {Debnath, Sashi and Singh, Saumya and Bedi, Anjan and Krishnamoorthy, Kothandam and Zade, Sanjio S.}
}
@article { ISI:000380038000012,
	title = {Site-selective synthesis and characterization of BODIPY-acetylene copolymers and their transistor properties},
	journal = {Journal of Polymer Science Part A-Polymer Chemistry},
	volume = {54},
	number = {13},
	year = {2016},
	month = {JUL},
	pages = {1978-1986},
	publisher = {WILEY-BLACKWELL},
	address = {111 RIVER ST, HOBOKEN 07030-5774, NJ USA},
	abstract = {<p>To study the effect of site-selective copolymerization of borondipyrromethene (BODIPY) with acetylene on the structural and optoelectronic properties, three copolymers P1-P3 were synthesized by the Sonogashira cross-coupling of BODIPY units with diacetylene and bromine capping through all the possible linkages: alpha-alpha (P1), alpha-beta (P2), and beta-beta (P3). The optoelectronic properties of the polymers were investigated systematically to understand the effect of site-selective polymerization. The HOMO levels of the polymers were significantly tuned from P1 to P3 with negligible change in the LUMO levels. Broadening of absorption spectra from P3 to P1 was observed because of increase in the extent of conjugation. Additionally, the charge transport properties of these polymers in organic thin-film transistors (OTFTs) revealed that P1 and P3 exhibited only p-type mobility, whereas P2 exhibited electron mobility. Notably, the further investigations of the surface morphology of polymer films by atomic force microscopy (AFM) unveiled that comb like nanostructural arrangements in P3 was beneficial for the charge-carrier mobility over the circular arrangements in P1 and P2. (C) 2016 Wiley Periodicals, Inc.</p>},
	keywords = {acetylene, BODIPY, DFT, low-band gap},
	issn = {0887-624X},
	doi = {10.1002/pola.28064},
	author = {Debnath, Sashi and Singh, Saumya and Bedi, Anjan and Krishnamoorthy, Kothandam and Zade, Sanjio S.}
}
